Baking normal then plugging into the normal channel of a shader results in flat shading
The blue color you're getting should be $RGB(0.5, 0.5, 1.0)$ which corresponds to a normal value of $&lt;0,0,1&gt;$. The normal vector has a range of $&lt;[-1, 1], [-1, 1], [0, 1]&gt;$ In Tangent space, as I understand it, the vector $&lt;0, 0, 1&gt;$ is perpendicular to the the surface. As the first value is changed, the vector tilts left and right. As the second vector is changed, the vector tilts up and down. The third value is adjusted so the length of the vector stays equal to 1. e.g. $z = \sqrt{1 - (x^2 + y^2)}$. Of course we should limit $ x^2 + y^2 \le 1 $.

This is illustrated by the &quot;Check Normal + Y&quot; matcap, which is based on the rendering of the normals of a sphere in Object Space. You can find an EXR version of this image in your Blender install folder under datafiles/studiolights/matcap. You'll see ... not what I expected ... I'm going to submit this now while I play with generating my own exr...
To be continued...